A method for recycling water and a water recycling device

ABSTRACT

The present inventive concept relates to a method for recycling water in a water recycling device, the method comprising: receiving used water via a drain; determining a water quality measure of the used water; if the water; quality measure of the water is above a first quality threshold, feeding the used water to a valve arrangement; in the valve arrangement, forming water to be treated by providing external water, the used water or a combination of the external water and the used water; generating treated water by treating the water to be treated using a water treatment arrangement; and feeding the treated water to an outlet. The present inventive concept also relates to a water recycling device.

TECHNICAL FIELD

The apparatuses, systems and methods described herein generally relatesto water recycling. More particularly, concepts for improved hygienicconditions in water recycling applications are being presented.

BACKGROUND

In many parts of the world, clean water is becoming a scarce commodity.Consequently, systems for purification and recycling of water has foundapplications across many fields. Conventional water recycling devicescan be effective, but is often costly, and requires frequent maintenanceand major modifications to existing piping.

An example of a water recycling device is known from e.g. SE469413.However, there is still a need for improved water recycling devices interms of reliability of removal of contaminants, cost, and ease ofinstallation.

SUMMARY OF THE INVENTION

It is an object of the present inventive concept to mitigate, alleviateor eliminate one or more of the above-identified deficiencies in the artand disadvantages singly or in combination.

According to a first aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a method forrecycling water in a water recycling device, said method comprising:receiving used water via a drain; determining a water quality measure ofsaid used water; if said water quality measure of said used water isabove a first quality threshold, feeding said used water to a valvearrangement; in said valve arrangement, forming water to be treated byproviding external water, said used water or a combination of saidexternal water and said used water; generating treated water by treatingsaid water to be treated using a water treatment arrangement; andfeeding said treated water to an outlet.

The step of forming water to be treated by providing external water,said used water or a combination of said external water and said usedwater, may comprise sub-steps of providing only said external water forforming said water to be treated if said water quality measure is belowsaid first quality threshold, or providing only said used water forforming said water to be treated if said water quality measure is abovesaid first quality threshold

The step of forming water to be treated by providing external water,said used water or a combination of said external water and said usedwater, may comprise sub-steps of providing only said external water forforming said water to be treated if said water quality measure is belowsaid first quality threshold and a second quality threshold, providingsaid combination of said external water and said used water for formingsaid water to be treated if said water quality measure is above saidfirst quality threshold but below said second quality threshold, orproviding only said used water for forming said water to be treated ifsaid water quality measure is above said first quality threshold andsaid second quality threshold.

The step of generating treated water by treating said water to betreated using a water treatment arrangement may comprise sub-steps offiltering said water to be treated, and reducing a harmful effect ofmicroorganisms in said water to be treated by using UV light.

According to a second aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a water recyclingdevice comprising: an outlet configured to output treated water; a drainfor collecting used water output from said outlet; a return path inliquid communication with said drain; a treatment path in liquidcommunication with said return path and said outlet; a external waterpath in liquid communication with said treatment path, said externalwater path being connected to a external water outlet; a valvearrangement configured to accept as inputs said used water from saidreturn path and/or external water from said external water path, saidvalve arrangement being placed between said return path and saidtreatment path, said valve arrangement being configured to direct saidinputs to said treatment path, said valve arrangement being configuredto mix said external water with said water from said return path; acirculation pump for providing a flow in said water recycling device;and a water treatment arrangement placed downstream of said valvearrangement.

The water recycling device may comprise a heating arrangement placeddownstream of and/or combined with said water treatment arrangement.

The heating arrangement may be combined with a UV light treatmentarrangement into a single piece of equipment

The water treatment arrangement may comprise a filter arrangement.

The water recycling device may comprise a valve discard path configuredto discharge water from said water recycling device, and said valvearrangement may be further configured to direct said water from saidreturn path to said valve discard path.

The valve arrangement may comprise at least a first and a second valvearrangement, and said first valve may be configured to accept as inputsaid used water from said return path, said first valve arrangement maybe configured to direct said used water from said return path to saidtreatment path, and said second valve arrangement may accept as inputsaid external water from said external water path, said second valvearrangement may be configured to direct said external water to saidtreatment path.

The first valve arrangement may be configured to direct said used waterfrom said return path to said valve discard path

The drain may comprise a drain discard path configured to discharge usedwater from said water recycling device.

The water recycling device may comprise a sensor arrangement configuredto measure a water quality parameter in water in the water recyclingdevice.

The sensor arrangement may comprise an electrical conductivity sensorand a UV-sensor.

The UV sensor may be arranged in said heating arrangement.

According to a third aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a waterrecirculating shower comprising a water recycling device according tothe second aspect of the inventive concept.

Other objectives, features and advantages of the present inventiveconcept will appear from the following detailed disclosure, from theattached claims as well as from the drawings.

Generally, all terms used in the claims are to be interpreted accordingto their ordinary meaning in the technical field, unless explicitlydefined otherwise herein. All references to “a/an/the [element, device,component, means, step, etc]” are to be interpreted openly as referringto at least one instance of said element, device, component, means,step, etc., unless explicitly stated otherwise. The steps of any methoddisclosed herein do not have to be performed in the exact orderdisclosed, unless explicitly stated.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as additional objects, features and advantages of thepresent inventive concept, will be better understood through thefollowing illustrative and non-limiting detailed description ofdifferent embodiments of the present inventive concept, with referenceto the appended drawings, wherein:

FIG. 1 schematically illustrates a conventional recirculation loop forrecycling water in a shower;

FIG. 2 schematically illustrates an example of a water recycling device;

FIG. 3 schematically illustrates an example of a water recycling device;

FIGS. 4-6 schematically illustrates flow directions in a water recyclingdevice.

FIG. 7 is a flow chart diagram of a method for recycling water in awater recycling device.

DETAILED DESCRIPTION

The present disclosure describes a water recycling device and methodsrelated to the same. Initially, some terminology may be defined toprovide clarification for the following disclosure.

In general, it has been realized by the inventors that hygienicconditions in a water recycling device can be improved by not allowingused water not adequate for recycling to contaminate external water inthe water recycling device. Further, it has been realized that hygienicconditions in a water recycling device can be improved by allowing waterfrom an external water source to pass a water treatment arrangement.

Throughout the present disclosure, reference is made to “externalwater”. External water could be for example tap water or similar. Theterm “external water” may herein be used for water entering the waterrecycling device from an external water source. The quality of externalwater may vary between applications. Further, the quality of externalwater may vary between different countries.

Throughout the present disclosure, reference is made to “treated water”as well as “used water”. Treated water may be water which has passed awater treatment arrangement and/or a heating arrangement. Treated waterwhich leaves an outlet of the water recycling device may be referred toas used water.

Throughout the present disclosure, reference is made to different paths.Such paths may be for example pipes for transporting water.

Throughout the present disclosure, references are made to features beingarranged “downstream” and/or “upstream” of certain features. The flowdirection to which the terms “downstream” and “upstream” refer should beunderstood to be a flow direction from the drain to the outlet. In otherwords, the “stream” referred to in the terms “downstream” and “upstream”is a stream flowing from the drain to the outlet.

Throughout the present disclosure, reference is made to a “cleaning” ofthe water recycling device. In this context, cleaning may refer to aflushing of the water recycling device, and/or a flushing and a cleaningof the water recycling device with a cleaning agent.

It is to be understood that a water recycling device may refer to awater recirculation device.

With reference to FIG. 1, a conventional recirculation loop 100 forrecycling water in a shower is shown. The recirculation loop 100comprises a drain 104 for collecting water emitted from a nozzle 102.The water collected by the drain 104 is directed to a valve 106 which isconfigured to direct the water either to a discard water pipe 108 ortowards the nozzle 102. A pump 110 provides a flow towards a valve 107,which accepts as inputs the collected water and potable water from apotable water source 112. The collected water can then be mixed with thepotable water, and emitted through the nozzle 102. In some cases, thepotable water may be exchanged for water being non-potable.

With reference to FIG. 2, a water recycling device 200 is shown. Thewater recycling device 200 comprises an outlet 238 configured to outputwater. The outlet 238 may be a showerhead, a nozzle, or the like. Thewater recycling device further comprises a drain 216 for collecting thewater output by the outlet, a return/evacuation path (R/E path) 220 inliquid communication with the drain 216, wherein the R/E path 220comprises an inlet 218 for receiving water collected by the drain 216.Water collected by the drain 216 may hereafter be referred to as usedwater. The R/E path is in liquid communication with a return path 222.The return path 222 is in liquid communication with a treatment path230. The treatment path is in liquid communication with the outlet 238.External water may enter the water recycling device via an externalwater path 224 in liquid communication with the treatment path 230,wherein the external water path 224 is connected to a external watersource. Water in the treatment path 230 may hereafter be referred to aswater to be treated. A valve arrangement 226 may be placed between thereturn path 222 and the treatment path 230. The valve arrangement 226may be configured to accept as inputs water from the return path, forexample used water, and/or external water from the external water path.The valve arrangement 226 may be configured to direct the inputs to thetreatment path 230. The valve arrangement 226 may be configured to mixthe external water with the water from the return path, for example theused water. The valve arrangement may comprise a valve discard path 240.The valve discard path may be configured to discharge water from thewater recycling device 200. A circulation pump 228 may be placeddownstream of the valve arrangement 226. The circulation pump 228 mayprovide for at least part of a flow of water in said water recyclingdevice 200. A water treatment arrangement 232 may be placed downstreamof the valve arrangement 226. The water treatment arrangement 232 maycomprise a filter arrangement and/or a UV light treatment arrangement.The water treatment arrangement 232 may comprise at least one filter,such as a nanofilter, a microfilter, or a nanofilter and a microfilter.The water treatment arrangement 232 may comprise at least one particlefilter and at least one microbiological filter. The water treatmentarrangement 232 may comprise at least one active substance for reducingharmful effects of microorganisms in water passing the water treatmentarrangement 232. Such an active substance may for example be containedwithin a filter media of the filter, and/or be released to the waterinside the water treatment arrangement 232. Water which has been treatedby the water treatment arrangement 232 may hereafter be referred to astreated water.

A heating arrangement 236 may be placed downstream of the watertreatment arrangement 232. By first reducing harmful effects ofmicroorganisms in water in the water recycling device 200 andsubsequently heat the water in the water recycling device 200, the riskfor microbiological growth is reduced compared to if the water, forexample being a combination of used water and external water, is firstheated and then treated, i.e. filtered and UV-light treated. A reasonfor this being the case is that the heating arrangement may for exampleheat the water to a temperature where microbiological growth isfavorable. The heating arrangement 236 may heat water passing theheating arrangement 236. The heating arrangement 236 may comprise a UVlight treatment arrangement. The heating arrangement 236 may be combinedwith the water treatment arrangement 232. The heating arrangement 236may comprise a UV sensor configured to detect UV light emitted from theUV light treatment arrangement after the UV light has passed throughwater contained within the heating arrangement 236. The heatingarrangement 236 may comprise a single piece of equipment for heating andUV light treating water. The heating arrangement 236 may provide atreatment of water. For example, the UV device may assist in reducingthe harmful effects of microorganisms present in the water passing theheating arrangement 236. Thus, water which has passed the heatingarrangement 236 may be referred to as treated water.

Still referring to FIG. 2, the water recycling device 200 may comprisean evacuation path 234 in liquid communication with the treatment path230. An inlet of the evacuation path 234 may be placed downstream of thecirculation pump. An inlet of the evacuation path 234 may be placedupstream of the water treatment arrangement 232. The evacuation path 234may comprise an evacuation valve arrangement configured to regulate aflow of water from the treatment path into the evacuation path. Theevacuation path 234 may be in liquid communication with the R/E path220. The R/E path 220 may be configured to direct water received fromthe evacuation path 234, to the drain via the inlet of the R/E path 220.

The water recycling device 200 may be configured to heat water in theheating arrangement 236 and subsequently drain the heated water via theevacuation path to the R/E path 220.

The R/E path 220 may be configured to be in a first state, wherein waterin the R/E path is allowed to flow in a direction away from the drain216. The first state of the R/E path 220 may be achieved by not allowingwater to flow through the evacuation path 234.

The R/E path 220 may be configured to be in a second state, whereinwater in the R/E path is allowed to flow in a direction towards thedrain 216. The second state of the R/E path 220 may be achieved byhaving the valve arrangement 226 set to accept only external water viathe external water path 224 as input, by having the circulation pump 228in operation, and by allowing water to flow through the evacuation path234. Another example of achieving the second state of the R/E path 220is by having the circulation pump 228 stopped, not accepting externalwater via the external water path 224 as input, and by allowing water toflow through the evacuation path 234.

Below, a number of advantages with the arrangement according to thepresent disclosure is presented. Reference will be made to used water,external water, and treated water. However, it is to be understood thatthese types of water may be interchangeable, and that any combination ofexternal, used, and treated water is possible within the scope of thepresent disclosure.

An advantage with an arrangement according to the present disclosure isthat a water quality measure of the used water collected by the drain216 may be performed in the drain 216. Consequently, a decision may bemade whether to recycle the used water, and thus direct the water viathe inlet 218 to the water treatment arrangement 232, or if the usedwater should be discarded via the drain discard path 242. If the wateris deemed to be inadequate for recycling, for example if a water qualitymeasure of the used water is below a first quality threshold, the usedwater may be directed to the drain discard path 242. The used water thusnever enters the return path 222 leading to the valve arrangement 226where external water is input via the external water path 224. As aresult, a risk of used water having a water quality measure below afirst quality threshold contaminating the external water is reduced.

Another advantage with an arrangement according to the presentdisclosure is that external water input via the external water path 224to the valve arrangement 226 may be treated in the water treatmentarrangement 232 before being output by the outlet 238. Thus, a risk ofallowing water containing contaminants to be output by the outlet 238 isreduced.

Yet another advantage with an arrangement according to the presentdisclosure is that water in at least part of the treatment path 230,such as water in a part of the treatment path 230 being upstream of theinlet of the evacuation path 234, and/or water in the water treatmentarrangement 232, and/or water in the heating arrangement 236, may drainvia the evacuation path 234, via the return path 222, and via the R/Epath 220 to the drain 216. By doing this, water may be prevented fromstanding inside the water treatment arrangement 232. In other words, thewater recycling device 200 may be emptied. In one example water may beheated in the heating arrangement 236 and subsequently drained, throughthe water treatment arrangement 232, via the evacuation path 234 and theR/E path 220 to the drain 216. This process may be repeated a number oftimes until a desired effect has been reached. Such a desired effect mayfor example be a reduction of contaminants in the water treatmentarrangement 232. In this context, contaminants should be given a broadinterpretation, meaning any kind of substance harmful to humans or tothe functionality of the water recycling device. The process of drainingwater from the water recycle device may be automated and/or scheduled tobe performed at specific intervals. Hereby, the water treatmentarrangement 232, evacuation path 234, R/E path 220 and drain 216 may beflushed with heated water. Heated water may in some cases provide a moreefficient flushing and/or cleaning compared to water which has not beenheated. The water recycling device 200 may be arranged such thatevacuation of the water recycling device 200 may be performed usinggravity. For example, the water recycling device 200 may be arrangedsuch that no water traps are formed in the different paths of the waterrecycling device 200. Further, the water recycling device 200 may beconfigured to be installed such that the heating arrangement 236 isarranged above the water treatment arrangement 232 with respect togravity. Similarly, the evacuation path 234 may be arranged above theR/E path 220 with respect to gravity. In one example, the circulationpump 228, and/or another pump arranged in the water recycling device200, may provide for a flow of water such that the water recyclingdevice 200 can be emptied.

Yet another advantage with an arrangement according to the presentdisclosure is that external water may enter the valve arrangement 226,flow via the treatment path 230 to the inlet of the evacuation path 234,and be directed to the drain 216 via the return path 222 and R/E path220. Hereby, the water recycling device 200 may be flushed with externalwater. For example, the drain 216 may be flushed by external water. Thedrain 216 may for example comprise a pre-filter for filtering watercollected from the outlet 238, such as used water. The pre-filter may bea mesh filter. In this case yet another advantage is that the pre-filtermay be flushed by external water. The water recycling device 200 maycomprise a sensor arrangement. The sensor arrangement may be arranged inthe drain 216. The sensor arrangement may be configured to measure anumber of water quality parameters in water in the water recyclingdevice and/or in water collected by the drain 216. The sensorarrangement may be configured to determine a water quality measure ofwater in the water recycling device. The sensor arrangement may comprisean electrical conductivity sensor and a UV-sensor. The electricalconductivity sensor may be arranged in the drain 216. The UV-sensor maybe arranged in the heating arrangement 236. In this case yet anotheradvantage is that external water may pass the sensor arrangement whenthe water recycling device is emptied, and thus external water may bemeasured by the sensor arrangement in order to set a reference value forthe number of water quality parameter.

Yet another advantage with an arrangement according to the presentdisclosure is that water in at least part of the treatment path 230, theevacuation path 234, and return path 222 may circulate in the treatmentpath 230, the evacuation path 234, and return path 222. In other words,at least part of the treatment path 230, the evacuation path 234, andreturn path 222 may form a loop. This water may for example be usedwater, external water, treated water, or any combination of used,external, and treated water. Hereby, the circulation pump 228 may beflushed.

Yet another advantage with an arrangement according to the presentdisclosure is that an internal cleaning and disinfection may be achievedby adding chemicals to the drain 216 and a disinfection cycle maysubsequently be triggered. The disinfection cycle may draw water,containing the chemicals, from the drain 216 into any of the watertreatment arrangement 232, circulation pump 228, valve arrangement 226,and heating arrangement 236, or any of the R/E path 220, return path222, evacuation path 234, and treatment path 230. The disinfection cyclemay be triggered from an application on a smart device, such as a smartphone.

The drain 216 may comprise a drain discard path 242. The drain discardpath 242 may be separated from the inlet of the R/E path 220, such thatused water which is not intended to be treated by the water treatmentarrangement 232, and thus not intended to be recycled, does not have toenter the inlet of the R/E path 220 in order to reach the drain discardpath 242. Hereby, contaminated water may be prevented from contaminatingany of the elements being arranged downstream of the inlet of the R/Epath 220.

Referring now to FIG. 3, a water recycling device 300 similar to thewater recycling device 200 described in conjunction with FIG. 2 isillustrated. It is to be understood that the water recycling device 300may comprise any of the features described above in conjunction withFIG. 2. The water recycling device 300 may comprise a first and a secondvalve arrangement 326, 327. The first valve arrangement 326 may beconfigured to accept as input the used water from the return path 322.The first valve arrangement may be configured to direct the used waterfrom the return path 322 to the treatment path 330. The second valvearrangement 327 may accept as input the external water from the externalwater path 324. The second valve arrangement 327 may be configured todirect the external water to the treatment path 330. The second valvearrangement 327 may be configured to direct the used water received fromthe first valve arrangement 326 to the treatment path 330. The firstvalve arrangement 326 may be configured to direct the used water fromthe return path 322 to the valve discard path 340.

Referring now to FIGS. 4-6, flow directions in a water recycling deviceare illustrated. Referring first to FIG. 4, when outputting water fromthe water recycling device, used water may be collected by the drain andenter the R/E path via the inlet of the R/E path. The used water maythen be directed to the return path, and the valve arrangement. Usedwater, and only used water, may thus be directed to the water treatmentarrangement and output by the outlet of the water recycling device. Thismay for example be the case if a water quality measure of the used wateris above a first quality threshold and a second quality threshold. Atthe valve arrangement, external water may enter the water recyclingdevice. This may for example be the case if a water quality measure ofthe used water is above the first quality threshold, but below a secondquality threshold. In other words, a combination of used water andexternal water is used. It is to be understood that it is possible touse only used water, only external water, or a combination of the two.External water, and only external water, may for example be used if awater quality measure of the used water below a first quality threshold.Water to be treated may then enter the treatment path via thecirculation pump and be directed to the water treatment arrangement.Treated water may then enter the heating arrangement, and subsequentlybe output from the outlet.

It is also possible to direct used water to the evacuation path (notshown). In this case, used water in the treatment path is first allowedto leave the treatment path via the evacuation path, the R/E path, andthe drain, and optionally via the outlet in case any used water hasalready passed the inlet of the evacuation path. External water may thenenter the valve arrangement and subsequently enter the treatment pathand be output from the outlet via the water treatment arrangement.Hereby, it is possible to discharge used water which is for any reasondeemed to be inadequate for recycling, for example if a water qualitymeasure of the used water is below a first quality threshold.

Yet another possibility is for used water to enter the drain, andsubsequently enter the drain discard pipe. This may for example be thecase if the used water is for any reason deemed to be inadequate forrecycling, for example if a water quality measure of the used water isbelow the first quality threshold and the second quality threshold. Inthis case used water never enters the inlet of the R/E path. Instead,external water may enter the valve arrangement, and subsequently enterthe treatment path and be output from the outlet via the water treatmentarrangement.

Yet another possibility is to fill the water recycling device withwater. For example, external water may be introduced to the waterrecycling device. This may be achieved by setting the valve arrangementto accept external water as input, the evacuation valve arrangement toprevent a flow of water into the evacuation path, and by the circulationpump providing a flow of water in the water recycling device. Externalwater may be allowed to fill the water recycling device to a level suchthat external water is introduced into the heating arrangement.

Referring now to FIG. 5, the evacuation valve arrangement may be set toallow a flow of water into the evacuation path, such that the waterrecycling device may be emptied. The circulation pump may in this casebe turned off. Water may thus drain from the treatment path via theheating arrangement, the water treatment arrangement, the evacuationpath, and the R/E path to the drain and subsequently to the draindiscard pipe. When evacuating the water recycling device, air may bedrawn through the outlet in order to equalize a pressure inside thewater recycling device. The air drawn through the outlet may assist inkeeping the water treatment arrangement dry, thus reducing thepossibility of growth of microorganisms in the water treatmentarrangement.

Referring now to FIG. 6, used water and/or external water may be loopedthrough the treatment path, the evacuation path, and the return path.This may be achieved by first providing used and/or external water tothe water recycling device. Subsequently, the valve arrangement may beset to only accept water received from the return path. The evacuationvalve arrangement may be set to allow a flow of water into theevacuation path. The circulation pump may provide a flow for loopingwater through the treatment path, the evacuation path, and the returnpath.

Referring now to FIG. 7, a method for recycling water in a waterrecycling device is illustrated in a flow chart diagram. The methodcomprises the step 742 of receiving used water via a drain; the step 744of determining a water quality measure of the used water; the step 746,if the water quality measure of the used water is above a first qualitythreshold, feeding the used water to a valve arrangement; the step 748of, in said valve arrangement, forming water to be treated by providingexternal water, the used water or a combination of the external waterand the used water; the step 750 of generating treated water by treatingthe water to be treated using a water treatment arrangement; and thestep 752 of feeding the treated water to an outlet.

A method for recycling water in a water recycling device is describedbelow. The water recycling device may comprise an outlet configured tooutput treated water; a drain for collecting used water output from saidoutlet; a return path in liquid communication with said drain; atreatment path in liquid communication with said return path and saidoutlet; an external water path in liquid communication with saidtreatment path, said external water path being connected to an externalwater outlet; a valve arrangement configured to accept as inputs saidused water from said return path and/or external water from saidexternal water path, said valve arrangement being placed between saidreturn path and said treatment path, said valve arrangement beingconfigured to direct said inputs to said treatment path, said valvearrangement being configured to mix said external water with said waterfrom said return path; a circulation pump for providing a flow in saidwater recycling device; and a water treatment arrangement placeddownstream of said valve arrangement. The method may comprise receivingused water via a drain; determining a water quality measure of the usedwater; if said water quality measure of the used water is above a firstquality threshold, feeding the used water to a valve arrangement; in thevalve arrangement, forming water to be treated by providing externalwater, the used water or a combination of the external water and theused water; generating treated water by treating the water to be treatedusing a water treatment arrangement; and feeding the treated water to anoutlet.

The step of forming water to be treated by providing external water, theused water or a combination of the external water and the used water,may further comprise sub-steps of providing only the external water forforming the water to be treated if the water quality measure is belowthe first quality threshold and a second quality threshold; providingthe combination of the external water and the used water for forming thewater to be treated if the water quality measure is above the firstquality threshold but below the second quality threshold; or providingonly the used water for forming the water to be treated if the waterquality measure is above the first quality threshold and the secondquality threshold.

The step of generating treated water by treating the water to be treatedusing a water treatment arrangement may further comprise sub-steps offiltering the water to be treated; and reducing a harmful effect ofmicroorganisms in the water to be treated by using UV light.

The water quality measure may for example be a measure of electricalconductivity in the used water. The water quality measure may bedetected in used water in the drain of the water recycling device.

The inventive concept has mainly been described above with reference toa few embodiments. However, as is readily appreciated by a personskilled in the art, other embodiments than the ones disclosed above areequally possible within the scope of the inventive concept, as definedby the appended patent claims.

LIST OF REFERENCE SIGNS

-   -   100 Recirculation loop    -   102 Nozzle    -   104 Drain    -   106 Valve    -   107 Valve    -   108 Discard water pipe    -   110 Pump    -   112 Potable water source    -   200 Water recycling device    -   216 Drain    -   218 Inlet    -   220 Return/Evacuation path    -   222 Return path    -   224 External water path    -   226 Valve arrangement    -   228 Circulation pump    -   230 Treatment path    -   232 Water treatment arrangement    -   234 Evacuation path    -   236 Heating arrangement    -   238 Outlet    -   240 Valve discard path    -   242 Drain discard path    -   300 Water recycling device    -   322 Return path    -   324 External water path    -   326 First valve arrangement    -   327 Second valve arrangement    -   330 Treatment path    -   340 Valve discard path    -   742 Step of receiving used water    -   744 Step of determining a water quality measure    -   746 Step of feeding used water to a valve arrangement    -   748 Step of forming water to be treated    -   750 Step of generating treated water    -   752 Step of feeding treated water to an outlet

The disclosure made in the following paragraphs relates to a relatedaspect of the inventive concept presented above. The apparatuses,systems and methods described below generally relates to waterrecycling. More particularly, concepts for improved hygienic conditionsin water recycling applications are being presented.

In many parts of the world, clean water is becoming a scarce commodity.Consequently, systems for purification and recycling of water has foundapplications across many fields. Conventional water recycling devicescan be effective, but is often costly, and requires frequent maintenanceand major modifications to existing piping.

An example of a water recycling device is known from e.g. SE469413.However, there is still a need for improved water recycling devices interms of reliability of removal of contaminants, cost, and ease ofinstallation.

It is an object of the present inventive concept to mitigate, alleviateor eliminate one or more of the above-identified deficiencies in the artand disadvantages singly or in combination.

According to a fourth aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a water recyclingdevice comprising: an outlet configured to output treated water; a drainfor collecting used water output from the outlet; a return/evacuationpath in liquid communication with the drain, wherein thereturn/evacuation path comprises an inlet for receiving water collectedby the drain; a return path in liquid communication with thereturn/evacuation path; a treatment path in liquid communication withthe return path and the outlet; an external water path in liquidcommunication with the treatment path, the external water path beingconnected to an external water outlet; a valve arrangement configured toaccept as inputs used water from the return path and/or external waterfrom the external water path, the valve arrangement being placed betweenthe return path and the treatment path, the valve arrangement beingconfigured to direct the inputs to the treatment path, the valvearrangement being configured to mix the external water with the usedwater from the return path; a circulation pump for providing a flow inthe water recycling device; and a water treatment arrangement placeddownstream of the valve arrangement.

The water recycling device may comprise a heating arrangement placeddownstream of the water treatment arrangement.

The water recycling device may comprise an evacuation path in liquidcommunication with the treatment path, wherein the evacuation path isplaced downstream of the valve arrangement and upstream of the watertreatment arrangement.

The evacuation path may comprise an evacuation valve arrangementconfigured to regulate a flow of water from the treatment path into theevacuation path.

The evacuation path may be in liquid communication with thereturn/evacuation path.

The water recycling device may be configured to heat water in theheating arrangement and subsequently drain the heated water via theevacuation path to the return/evacuation path.

The water recycling device may be configured to circulate water in atleast part of the treatment path, the evacuation path, and the returnpath.

The return/evacuation path may be configured to direct water receivedfrom the evacuation path to the drain via the inlet of thereturn/evacuation path.

The drain may comprise a drain discard path configured to dischargewater from the water recycling device.

The return/evacuation path may be configured to be in a first state,wherein water in the return/evacuation path is allowed to flow in adirection away from the drain, and a second state, wherein water in thereturn/evacuation path is allowed to flow in a direction towards thedrain.

The water recycling device may comprise a sensor arrangement configuredto measure a water quality parameter in water in the water recyclingdevice.

The sensor arrangement may comprise an electrical conductivity sensorand a UV-sensor.

According to a fifth aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a waterrecirculating shower comprising a water recycling device according tothe first aspect of the inventive concept.

According to a sixth aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a method forevacuating a water recycling device, the water recycling devicecomprising: an outlet configured to output treated water; a drain forcollecting used water output from the outlet; a return/evacuation pathin liquid communication with the drain, wherein the return/evacuationpath comprises an inlet for receiving water collected by the drain; areturn path in liquid communication with the return/evacuation path; atreatment path in liquid communication with the return path and theoutlet; an external water path in liquid communication with thetreatment path, the external water path being connected to an externalwater outlet; a valve arrangement, wherein the valve arrangement isconfigured to accept as inputs used water from the return path and/orexternal water from the external water path, the valve arrangement beingplaced between the return path and the treatment path, the valvearrangement being configured to direct the inputs to the treatment path,the valve arrangement being configured to mix the external water withthe used water from the return path; a circulation pump for providing aflow in the water recycling device; a water treatment arrangement placeddownstream of the valve arrangement; and an evacuation path in liquidcommunication with the treatment path, wherein the evacuation path isplaced downstream of the circulation pump and upstream of the watertreatment arrangement; wherein the method comprises the steps of:feeding water in the water recycling device to the drain via theevacuation path and/or the return/evacuation path.

The step of feeding water in the water recycling device to the drain viathe evacuation path and/or the return/evacuation path may beaccomplished by gravity.

According to a seventh aspect of the inventive concept, these and otherobjects are achieved in full, or at least in part, by a method forcleaning a water recycling device, the water recycling devicecomprising: an outlet configured to output treated water; a drain forcollecting used the water output from the outlet; a return/evacuationpath in liquid communication with the drain, wherein thereturn/evacuation path comprises an inlet for receiving water collectedby the drain; a return path in liquid communication with thereturn/evacuation path; a treatment path in liquid communication withthe return path and the outlet; an external water path in liquidcommunication with the treatment path, the external water path beingconnected to an external water outlet; a valve arrangement, wherein thevalve arrangement is configured to accept as inputs used water from thereturn path and/or external water from the external water path, thevalve arrangement being placed between the return path and the treatmentpath, the valve arrangement being configured to direct the inputs to thetreatment path, the valve arrangement being configured to mix theexternal water with the used water from the return path; a circulationpump for providing a flow in the water recycling device; a watertreatment arrangement placed downstream of the valve arrangement; and anevacuation path in liquid communication with the treatment path, whereinthe evacuation path is placed downstream of the circulation pump andupstream of the water treatment arrangement; the method comprising thesteps of: providing the water recycling device with the used water, theexternal water, or a combination of the used water and the externalwater; and evacuating the water recycling device according to the secondaspect of the inventive concept.

The step of providing the water recycling device with the used water,the external water, or the combination of the used water and theexternal water may comprise a sub-step of at least partly filling thewater treatment arrangement with the used water, the external water, ora combination of the used water and the external water.

The step of providing the water recycling device with the used water,the external water, or the combination of the used water and theexternal water may comprise a sub-step of circulating the used water,the external water, or the combination of the used water and theexternal water in the evacuation path, the return path, and at leastpart of the treatment path.

The water recycling device may comprise a heater arrangement placeddownstream of the water treatment arrangement and/or combined with thewater treatment arrangement, and the step of providing the waterrecycling device with the used water, the external water, or thecombination of the used water and the external water may comprise asub-step of heating the used water, the external water, or thecombination of the used water and the external water in the heatingarrangement.

Other objectives, features and advantages of the present inventiveconcept will appear from the following detailed disclosure, from theattached clauses as well as from the drawings.

Generally, all terms used in the clauses are to be interpreted accordingto their ordinary meaning in the technical field, unless explicitlydefined otherwise herein. All references to “a/an/the [element, device,component, means, step, etc]” are to be interpreted openly as referringto at least one instance of said element, device, component, means,step, etc., unless explicitly stated otherwise. The steps of any methoddisclosed herein do not have to be performed in the exact orderdisclosed, unless explicitly stated.

The above, as well as additional objects, features and advantages of thepresent inventive concept, will be better understood through thefollowing illustrative and non-limiting detailed description ofdifferent embodiments of the present inventive concept, with referenceto the appended drawings, wherein:

FIG. 8 schematically illustrates a conventional recirculation loop forrecycling water in a shower;

FIG. 9 schematically illustrates an example of a water recycling device;

FIG. 10 schematically illustrates an example of a water recyclingdevice;

FIGS. 11-13 schematically illustrates flow directions in a waterrecycling device.

FIG. 14 is a flow chart diagram of a method for evacuating a waterrecycling device.

The present disclosure describes a water recycling device and methodsrelated to the same. Initially, some terminology may be defined toprovide clarification for the following disclosure.

In general, it has been realized by the inventors that hygienicconditions in a water recycling device can be improved by draining waterfrom the water recycling device when it is not used for recycling water,such as between uses, or at certain time intervals. By doing this, watermay be prevented from becoming stagnant. It has further been realizedthat external water and/or water collected in a drain of the waterrecycling device may be used to flush the water recycling device.

Throughout the present disclosure, reference is made to “externalwater”. External water could be for example tap water or similar. Theterm “external water” may herein be used for water entering the waterrecycling device from an external water source. The quality of externalwater may vary between applications. Further, the quality of externalwater may vary between different countries.

Throughout the present disclosure, reference is made to “treated water”as well as “used water”. Treated water may be water which has passed awater treatment arrangement and/or a heating arrangement. Treated waterwhich leaves an outlet of the water recycling device may be referred toas used water.

Throughout the present disclosure, reference is made to different paths.Such paths may be for example pipes for transporting water.

Throughout the present disclosure, references are made to features beingarranged “downstream” and/or “upstream” of certain features. The flowdirection to which the terms “downstream” and “upstream” refer should beunderstood to be a flow direction from the drain to the outlet. In otherwords, the “stream” referred to in the terms “downstream” and “upstream”is a stream flowing from the drain to the outlet.

Throughout the present disclosure, reference is made to a “cleaning” ofthe water recycling device. In this context, cleaning may refer to aflushing of the water recycling device, and/or a flushing and a cleaningof the water recycling device with a cleaning agent.

Throughout the present disclosure, a “water quality parameter” may beinterchangeably used with a “water quality measure”.

It is to be understood that a water recycling device may refer to awater recirculation device.

With reference to FIG. 8, a conventional recirculation loop 1100 forrecycling water in a shower is shown. The recirculation loop 1100comprises a drain 1104 for collecting water emitted from a nozzle 1102.The water collected by the drain 1104 is directed to a valve 1106 whichis configured to direct the water either to a discard water pipe 1108 ortowards the nozzle 1102. A pump 1110 provides a flow towards a valve1107, which accepts as inputs the collected water and potable water froma potable water source 1112. The collected water can then be mixed withthe potable water, and emitted through the nozzle 1102. In some cases,the potable water may be exchanged for water being non-potable.

With reference to FIG. 9, a water recycling device 1200 is shown. Thewater recycling device 1200 comprises an outlet 1238 configured tooutput water. The outlet 1238 may be a showerhead, a nozzle, or thelike. The water recycling device further comprises a drain 1216 forcollecting the water output by the outlet, a return/evacuation path (R/Epath) 1220 in liquid communication with the drain 1216, wherein the R/Epath 1220 comprises an inlet 1218 for receiving water collected by thedrain 1216. Water collected by the drain 1216 may hereafter be referredto as used water. The R/E path is in liquid communication with a returnpath1 222. The return path 1222 is in liquid communication with atreatment path 1230. The treatment path is in liquid communication withthe outlet 1238. External water may enter the water recycling device viaan external water path 1224 in liquid communication with the treatmentpath 1230, wherein the external water path 1224 is connected to anexternal water source. Water in the treatment path 1230 may hereafter bereferred to as water to be treated. A valve arrangement 1226 may beplaced between the return path 1222 and the treatment path 1230. Thevalve arrangement 1226 may be configured to accept as inputs water fromthe return path, for example used water, and/or external water from theexternal water path. The valve arrangement 1226 may be configured todirect the inputs to the treatment path 1230. The valve arrangement 1226may be configured to mix the external water with the water from thereturn path, for example the used water. The valve arrangement maycomprise a valve discard path 1240. The valve discard path may beconfigured to discharge water from the water recycling device 1200. Acirculation pump 1228 may be placed downstream of the valve arrangement1226. The circulation pump 1228 may provide for at least part of a flowof water in said water recycling device 1200. A water treatmentarrangement 1232 may be placed downstream of the valve arrangement 1226.The water treatment arrangement 1232 may comprise a filter arrangementand/or a UV light treatment arrangement. The water treatment arrangement1232 may comprise at least one filter, such as a nanofilter, amicrofilter, or a nanofilter and a microfilter. The water treatmentarrangement 1232 may comprise at least one particle filter and at leastone microbiological filter. The water treatment arrangement 1232 maycomprise at least one active substance for reducing harmful effects ofmicroorganisms in water passing the water treatment arrangement 1232.Such an active substance may for example be contained within a filtermedia of the filter, and/or be released to the water inside the watertreatment arrangement 1232. Water which has been treated by the watertreatment arrangement 1232 may hereafter be referred to as treatedwater.

A heating arrangement 1236 may be placed downstream of the watertreatment arrangement 1232. By first reducing harmful effects ofmicroorganisms in water in the water recycling device 1200 andsubsequently heat the water in the water recycling device 1200, the riskfor microbiological growth is reduced compared to if the water, forexample being a combination of used water and external water, is firstheated and then treated, i.e. filtered and UV-light treated. A reasonfor this being the case is that the heating arrangement may for exampleheat the water to a temperature where microbiological growth isfavorable. The heating arrangement 1236 may heat water passing theheating arrangement 1236. The heating arrangement 1236 may comprise a UVlight treatment arrangement. The heating arrangement 1236 may becombined with the water treatment arrangement 1232. The heatingarrangement 1236 may comprise a UV sensor configured to detect UV lightemitted from the UV light treatment arrangement after the UV light haspassed through water contained within the heating arrangement 1236. Theheating arrangement 1236 may comprise a single piece of equipment forheating and UV light treating water. The heating arrangement 1236 mayprovide a treatment of water. For example, the UV device may assist inreducing the harmful effects of microorganisms present in the waterpassing the heating arrangement 1236. Thus, water which has passed theheating arrangement 1236 may be referred to as treated water.

Still referring to FIG. 9, the water recycling device 1200 may comprisean evacuation path 1234 in liquid communication with the treatment path1230. An inlet of the evacuation path 1234 may be placed downstream ofthe circulation pump. An inlet of the evacuation path 1234 may be placedupstream of the water treatment arrangement 1232. The evacuation path1234 may comprise an evacuation valve arrangement configured to regulatea flow of water from the treatment path into the evacuation path. Theevacuation path 1234 may be in liquid communication with the R/E path1220. The R/E path 1220 may be configured to direct water received fromthe evacuation path 1234, to the drain via the inlet of the R/E path1220.

The water recycling device 1200 may be configured to heat water in theheating arrangement 1236 and subsequently drain the heated water via theevacuation path to the R/E path 1220.

The R/E path 1220 may be configured to be in a first state, whereinwater in the R/E path is allowed to flow in a direction away from thedrain 1216. The first state of the R/E path 1220 may be achieved by notallowing water to flow through the evacuation path 1234.

The R/E path 1220 may be configured to be in a second state, whereinwater in the R/E path is allowed to flow in a direction towards thedrain 1216. The second state of the R/E path 1220 may be achieved byhaving the valve arrangement 1226 set to accept only external water viathe external water path 1224 as input, by having the circulation pump1228 in operation, and by allowing water to flow through the evacuationpath 1234. Another example of achieving the second state of the R/E path1220 is by having the circulation pump 1228 stopped, not acceptingexternal water via the external water path 1224 as input, and byallowing water to flow through the evacuation path 1234.

Below, a number of advantages with the arrangement according to thepresent disclosure is presented. Reference will be made to used water,external water, and treated water. However, it is to be understood thatthese types of water may be interchangeable, and that any combination ofexternal, used, and treated water is possible within the scope of thepresent disclosure.

An advantage with an arrangement according to the present disclosure isthat a water quality measure of the used water collected by the drain1216 may be performed in the drain 1216. Consequently, a decision may bemade whether to recycle the used water, and thus direct the water viathe inlet 1218 to the water treatment arrangement 1232, or if the usedwater should be discarded via the drain discard path 1242. If the wateris deemed to be inadequate for recycling, for example if a water qualitymeasure of the used water is below a first quality threshold, the usedwater may be directed to the drain discard path 1242. The used waterthus never enters the return path 1222 leading to the valve arrangement1226 where external water is input via the external water path 1224. Asa result, a risk of used water having a water quality measure below afirst quality threshold contaminating the external water is reduced. Thewater quality measure may for example be a measure of electricalconductivity in the used water. The water quality measure may bedetected in used water in the drain of the water recycling device.

Another advantage with an arrangement according to the presentdisclosure is that external water input via the external water path 1224to the valve arrangement 1226 may be treated in the water treatmentarrangement 1232 before being output by the outlet 1238. Thus, a risk ofallowing water containing contaminants to be output by the outlet 1238is reduced.

Yet another advantage with an arrangement according to the presentdisclosure is that water in at least part of the treatment path 1230,such as water in a part of the treatment path 1230 being upstream of theinlet of the evacuation path 1234, and/or water in the water treatmentarrangement 1232, and/or water in the heating arrangement 1236, maydrain via the evacuation path 1234, via the return path 1222, and viathe R/E path 1220 to the drain 1216. By doing this, water may beprevented from standing inside the water treatment arrangement 1232. Inother words, the water recycling device 1200 may be emptied. In oneexample water may be heated in the heating arrangement 1236 andsubsequently drained, through the water treatment arrangement 1232, viathe evacuation path 1234 and the R/E path 1220 to the drain 1216. Thisprocess may be repeated a number of times until a desired effect hasbeen reached. Such a desired effect may for example be a reduction ofcontaminants in the water treatment arrangement 1232. In this context,contaminants should be given a broad interpretation, meaning any kind ofsubstance harmful to humans or to the functionality of the waterrecycling device. The process of draining water from the water recycledevice may be automated and/or scheduled to be performed at specificintervals. Hereby, the water treatment arrangement 1232, evacuation path1234, R/E path 1220 and drain 1216 may be flushed with heated water.Heated water may in some cases provide a more efficient flushing and/orcleaning compared to water which has not been heated. The waterrecycling device 1200 may be arranged such that evacuation of the waterrecycling device 1200 may be performed using gravity. For example, thewater recycling device 1200 may be arranged such that no water traps areformed in the different paths of the water recycling device 1200.Further, the water recycling device 1200 may be configured to beinstalled such that the heating arrangement 1236 is arranged above thewater treatment arrangement 1232 with respect to gravity. Similarly, theevacuation path 1234 may be arranged above the R/E path 1220 withrespect to gravity. In one example, the circulation pump 1228, and/oranother pump arranged in the water recycling device 1200, may providefor a flow of water such that the water recycling device 1200 can beemptied.

Yet another advantage with an arrangement according to the presentdisclosure is that external water may enter the valve arrangement 1226,flow via the treatment path 1230 to the inlet of the evacuation path1234, and be directed to the drain 1216 via the return path 1222 and R/Epath 1220. Hereby, the water recycling device 1200 may be flushed withexternal water. For example, the drain 1216 may be flushed by externalwater. The drain 1216 may for example comprise a pre-filter forfiltering water collected from the outlet 1238, such as used water. Thepre-filter may be a mesh filter. In this case yet another advantage isthat the pre-filter may be flushed by external water. The waterrecycling device 1200 may comprise a sensor arrangement. The sensorarrangement may be arranged in the drain 1216. The sensor arrangementmay be configured to measure a number of water quality parameters inwater in the water recycling device and/or in water collected by thedrain 1216. The sensor arrangement may be configured to determine awater quality measure of water in the water recycling device. The sensorarrangement may comprise an electrical conductivity sensor and aUV-sensor. The electrical conductivity sensor may be arranged in thedrain 1216. The UV-sensor may be arranged in the heating arrangement1236. In this case yet another advantage is that external water may passthe sensor arrangement when the water recycling device is emptied, andthus external water may be measured by the sensor arrangement in orderto set a reference value for the number of water quality parameter.

Yet another advantage with an arrangement according to the presentdisclosure is that water in at least part of the treatment path 1230,the evacuation path 1234, and return path 1222 may circulate in thetreatment path 1230, the evacuation path 1234, and return path 1222. Inother words, at least part of the treatment path 1230, the evacuationpath 1234, and return path 1222 may form a loop. This water may forexample be used water, external water, treated water, or any combinationof used, external, and treated water. Hereby, the circulation pump 1228may be flushed.

Yet another advantage with an arrangement according to the presentdisclosure is that an internal cleaning and disinfection may be achievedby adding chemicals to the drain 1216 and a disinfection cycle maysubsequently be triggered. The disinfection cycle may draw water,containing the chemicals, from the drain 1216 into any of the watertreatment arrangement 1232, circulation pump 1228, valve arrangement1226, and heating arrangement 1236, or any of the R/E path 1220, returnpath 1222, evacuation path 1234, and treatment path 1230. Thedisinfection cycle may be triggered from an application on a smartdevice, such as a smart phone.

The drain 1216 may comprise a drain discard path 1242. The drain discardpath 1242 may be separated from the inlet of the R/E path 1220, suchthat used water which is not intended to be treated by the watertreatment arrangement 1232, and thus not intended to be recycled, doesnot have to enter the inlet of the R/E path 1220 in order to reach thedrain discard path 1242. Hereby, contaminated water may be preventedfrom contaminating any of the elements being arranged downstream of theinlet of the R/E path 1220.

Referring now to FIG. 10, a water recycling device 1300 similar to thewater recycling device 1200 described in conjunction with FIG. 9 isillustrated. It is to be understood that the water recycling device 1300may comprise any of the features described above in conjunction withFIG. 9. The water recycling device 1300 may comprise a first and asecond valve arrangement 1326, 1327. The first valve arrangement 1326may be configured to accept as input the used water from the return path1322. The first valve arrangement may be configured to direct the usedwater from the return path 1322 to the treatment path 1330. The secondvalve arrangement 1327 may accept as input the external water from theexternal water path 324. The second valve arrangement 1327 may beconfigured to direct the external water to the treatment path 1330. Thesecond valve arrangement 1327 may be configured to direct the used waterreceived from the first valve arrangement 1326 to the treatment path1330. The first valve arrangement 1326 may be configured to direct theused water from the return path 1322 to the valve discard path 1340.

Referring now to FIGS. 11-13, flow directions in a water recyclingdevice are illustrated. Referring first to FIG. 11, when outputtingwater from the water recycling device, used water may be collected bythe drain and enter the R/E path via the inlet of the R/E path. The usedwater may then be directed to the return path, and the valvearrangement. Used water, and only used water, may thus be directed tothe water treatment arrangement and output by the outlet of the waterrecycling device. This may for example be the case if a water qualitymeasure of the used water is above a first quality threshold and asecond quality threshold. At the valve arrangement, external water mayenter the water recycling device. This may for example be the case if awater quality measure of the used water is above the first qualitythreshold, but below a second quality threshold. In other words, acombination of used water and external water is used. It is to beunderstood that it is possible to use only used water, only externalwater, or a combination of the two. External water, and only externalwater, may for example be used if a water quality measure of the usedwater below a first quality threshold. Water to be treated may thenenter the treatment path via the circulation pump and be directed to thewater treatment arrangement. Treated water may then enter the heatingarrangement, and subsequently be output from the outlet.

It is also possible to direct used water to the evacuation path (notshown). In this case, used water in the treatment path is first allowedto leave the treatment path via the evacuation path, the R/E path, andthe drain, and optionally via the outlet in case any used water hasalready passed the inlet of the evacuation path. External water may thenenter the valve arrangement and subsequently enter the treatment pathand be output from the outlet via the water treatment arrangement.Hereby, it is possible to discharge used water which is for any reasondeemed to be inadequate for recycling, for example if a water qualitymeasure of the used water is below a first quality threshold.

Yet another possibility is for used water to enter the drain, andsubsequently enter the drain discard pipe. This may for example be thecase if the used water is for any reason deemed to be inadequate forrecycling, for example if a water quality measure of the used water isbelow the first quality threshold and the second quality threshold. Inthis case used water never enters the inlet of the R/E path. Instead,external water may enter the valve arrangement, and subsequently enterthe treatment path and be output from the outlet via the water treatmentarrangement.

Yet another possibility is to fill the water recycling device withwater. For example, external water may be introduced to the waterrecycling device. This may be achieved by setting the valve arrangementto accept external water as input, the evacuation valve arrangement toprevent a flow of water into the evacuation path, and by the circulationpump providing a flow of water in the water recycling device. Externalwater may be allowed to fill the water recycling device to a level suchthat external water is introduced into the heating arrangement.

Referring now to FIG. 12, the evacuation valve arrangement may be set toallow a flow of water into the evacuation path, such that the waterrecycling device may be emptied. The circulation pump may in this casebe turned off. Water may thus drain from the treatment path via theheating arrangement, the water treatment arrangement, the evacuationpath, and the R/E path to the drain and subsequently to the draindiscard pipe. When evacuating the water recycling device, air may bedrawn through the outlet in order to equalize a pressure inside thewater recycling device. The air drawn through the outlet may assist inkeeping the water treatment arrangement dry, thus reducing thepossibility of growth of microorganisms in the water treatmentarrangement.

Referring now to FIG. 13, used water and/or external water may be loopedthrough the treatment path, the evacuation path, and the return path.This may be achieved by first providing used and/or external water tothe water recycling device. Subsequently, the valve arrangement may beset to only accept water received from the return path. The evacuationvalve arrangement may be set to allow a flow of water into theevacuation path. The circulation pump may provide a flow for loopingwater through the treatment path, the evacuation path, and the returnpath.

Referring now to FIG. 14, a method for evacuating a water recyclingdevice is illustrated in a flow chart diagram. The method comprises thestep 1742 of feeding water in the water recycling device to the drainvia the evacuation path and/or the return/evacuation path.

A method for evacuating a water recycling device is described below. Thewater recycling device may comprise an outlet configured to outputtreated water; a drain for collecting used water output from the outlet;a return/evacuation path in liquid communication with the drain, whereinthe return/evacuation path comprises an inlet for receiving watercollected by the drain; a return path in liquid communication with thereturn/evacuation path; a treatment path in liquid communication withthe return path and the outlet; an external water path in liquidcommunication with the treatment path, the external water path beingconnected to an external water outlet; a valve arrangement, wherein thevalve arrangement is configured to accept as inputs used water from thereturn path and/or external water from the external water path, thevalve arrangement being placed between the return path and the treatmentpath, the valve arrangement being configured to direct the inputs to thetreatment path, the valve arrangement being configured to mix theexternal water with the used water from the return path; a circulationpump for providing a flow in the water recycling device; a watertreatment arrangement placed downstream of the valve arrangement; and anevacuation path in liquid communication with the treatment path, whereinthe evacuation path is placed downstream of the circulation pump andupstream of the water treatment arrangement. The method may comprise thesteps of feeding water in the water recycling device to the drain viathe evacuation path and/or the return/evacuation path. The step offeeding water in the water recycling device to the drain via theevacuation path and/or the return/evacuation path may be accomplished bygravity.

A method for cleaning a water recycling device is described below. Thewater recycle device may comprise an outlet configured to output treatedwater; a drain for collecting used the water output from the outlet; areturn/evacuation path in liquid communication with the drain, whereinthe return/evacuation path comprises an inlet for receiving watercollected by the drain; a return path in liquid communication with thereturn/evacuation path; a treatment path in liquid communication withthe return path and the outlet; an external water path in liquidcommunication with the treatment path, the external water path beingconnected to an external water outlet; a valve arrangement, wherein thevalve arrangement is configured to accept as inputs used water from thereturn path and/or external water from the external water path, thevalve arrangement being placed between the return path and the treatmentpath, the valve arrangement being configured to direct the inputs to thetreatment path, the valve arrangement being configured to mix theexternal water with the used water from the return path; a circulationpump for providing a flow in the water recycling device; a watertreatment arrangement placed downstream of the valve arrangement; and anevacuation path in liquid communication with the treatment path, whereinthe evacuation path is placed downstream of the circulation pump andupstream of the water treatment arrangement. The method may comprise thesteps of providing the water recycling device with the used water, theexternal water, or a combination of the used water and the externalwater; and evacuating the water recycling device according to the methodfor evacuating a water recycling device as described above.

The step of providing the water recycling device with the used water,the external water, or a combination of the used water and the externalwater may comprise a sub-step of at least partly filling the watertreatment arrangement with the used water, the external water, or thecombination of the used water and the external water.

The step of providing the water recycling device with the used water,the external water, or the combination of the used water and theexternal water may comprise a sub-step of circulating the used water,the external water, or the combination of the used water and theexternal water in the evacuation path, the return path, and at leastpart of the treatment path.

The water recycling device may further comprise a heater arrangementplaced downstream of the water treatment arrangement and/or combinedwith the water treatment arrangement, and the step of providing thewater recycling device with the used water, the external water, or thecombination of the used water and the external water may comprise asub-step of heating the used water, the external water, or thecombination of the used water and the external water in the heatingarrangement.

The inventive concept has mainly been described above with reference toa few embodiments. However, as is readily appreciated by a personskilled in the art, other embodiments than the ones disclosed above areequally possible within the scope of the inventive concept, as definedby the appended patent claims.

LIST OF REFERENCE SIGNS

-   -   1100 Recirculation loop    -   1102 Nozzle    -   1104 Drain    -   1106 Valve    -   1107 Valve    -   1108 Discard water pipe    -   1110 Pump    -   1112 Potable water source    -   1200 Water recycling device    -   1216 Drain    -   1218 Inlet    -   1220 Return/Evacuation path    -   1222 Return path    -   1224 External water path    -   1226 Valve arrangement    -   1228 Circulation pump    -   1230 Treatment path    -   1232 Water treatment arrangement    -   1234 Evacuation path    -   1236 Heating arrangement    -   1238 Outlet    -   1240 Valve discard path    -   1242 Drain discard path    -   1300 Water recycling device    -   1322 Return path    -   1324 External water path    -   1326 First valve arrangement    -   1327 Second valve arrangement    -   1330 Treatment path    -   1340 Valve discard path    -   1742 Step of feeding water to drain via evacuation path and/or        return/evacuation path

CLAUSES

1. A water recycling device comprising:

-   -   an outlet configured to output treated water;    -   a drain for collecting used water output from said outlet;    -   a return/evacuation path in liquid communication with said        drain, wherein said return/evacuation path comprises an inlet        for receiving water collected by said drain;    -   a return path in liquid communication with said        return/evacuation path;    -   a treatment path in liquid communication with said return path        and said outlet;    -   an external water path in liquid communication with said        treatment path, said external water path being connected to an        external water outlet;    -   a valve arrangement configured to accept as inputs used water        from said return path and/or external water from said external        water path, said valve arrangement being placed between said        return path and said treatment path, said valve arrangement        being configured to direct said inputs to said treatment path,        said valve arrangement being configured to mix said external        water with said used water from said return path;    -   a circulation pump for providing a flow in said water recycling        device; and    -   a water treatment arrangement placed downstream of said valve        arrangement.

2. The water recycling device according to any one of the precedingclauses, further comprising a heating arrangement placed downstream ofsaid water treatment arrangement.

3. The water recycling device according to clause 1 or 2, furthercomprising an evacuation path in liquid communication with saidtreatment path, wherein said evacuation path is placed downstream ofsaid valve arrangement and upstream of said water treatment arrangement.

4. The water recycling device according to clause 3, wherein said waterrecycling device is configured to circulate water in at least part ofsaid treatment path, said evacuation path, and said return path.

5. The water recycling device according to any one of the precedingclauses, wherein said return/evacuation path is configured to be in afirst state, wherein water in said return/evacuation path is allowed toflow in a direction away from said drain, and a second state, whereinwater in said return/evacuation path is allowed to flow in a directiontowards said drain.

6. A water recirculating shower comprising a water recycling deviceaccording to any one of clauses 1 to 5.

7. A method for evacuating a water recycling device, said waterrecycling device comprising:

-   -   an outlet configured to output treated water;    -   a drain for collecting used water output from said outlet;    -   a return/evacuation path in liquid communication with said        drain, wherein said return/evacuation path comprises an inlet        for receiving water collected by said drain;    -   a return path in liquid communication with said        return/evacuation path;    -   a treatment path in liquid communication with said return path        and said outlet;    -   an external water path in liquid communication with said        treatment path, said external water path being connected to an        external water outlet;    -   a valve arrangement, wherein said valve arrangement is        configured to accept as inputs used water from said return path        and/or external water from said external water path, said valve        arrangement being placed between said return path and said        treatment path, said valve arrangement being configured to        direct said inputs to said treatment path, said valve        arrangement being configured to mix said external water with        said used water from said return path;    -   a circulation pump for providing a flow in said water recycling        device;    -   a water treatment arrangement placed downstream of said valve        arrangement; and    -   an evacuation path in liquid communication with said treatment        path, wherein said evacuation path is placed downstream of said        circulation pump and upstream of said water treatment        arrangement;    -   wherein said method comprises the steps of:    -   feeding water in said water recycling device to said drain via        said evacuation path and/or said return/evacuation path.

8. The method according to clause 7, wherein said step of feeding waterin said water recycling device to said drain via said evacuation pathand/or said return/evacuation path is accomplished by gravity.

9. A method for cleaning a water recycling device, said water recyclingdevice comprising:

-   -   an outlet configured to output treated water;    -   a drain for collecting used said water output from said outlet;    -   a return/evacuation path in liquid communication with said        drain, wherein said return/evacuation path comprises an inlet        for receiving water collected by said drain;    -   a return path in liquid communication with said        return/evacuation path;    -   a treatment path in liquid communication with said return path        and said outlet;    -   an external water path in liquid communication with said        treatment path, said external water path being connected to an        external water outlet;    -   a valve arrangement, wherein said valve arrangement is        configured to accept as inputs used water from said return path        and/or external water from said external water path, said valve        arrangement being placed between said return path and said        treatment path, said valve arrangement being configured to        direct said inputs to said treatment path, said valve        arrangement being configured to mix said external water with        said used water from said return path;    -   a circulation pump for providing a flow in said water recycling        device;    -   a water treatment arrangement placed downstream of said valve        arrangement; and    -   an evacuation path in liquid communication with said treatment        path, wherein said evacuation path is placed downstream of said        circulation pump and upstream of said water treatment        arrangement;    -   said method comprising the steps of:    -   providing said water recycling device with said used water, said        external water, or a combination of said used water and said        external water; and    -   evacuating said water recycling device according to the method        of clause 7 or 8.

10. The method for cleaning a water recycling device according to clause9, wherein said step of providing said water recycling device with saidused water, said external water, or said combination of said used waterand said external water comprises a sub-step of at least partly fillingsaid water treatment arrangement with said used water, said externalwater, or a combination of said used water and said external water.

11. The method for cleaning a water recycling device according to clause9 or 10, wherein said step of providing said water recycling device withsaid used water, said external water, or said combination of said usedwater and said external water comprises a sub-step of circulating saidused water, said external water, or said combination of said used waterand said external water in said evacuation path, said return path, andat least part of said treatment path.

12. The method for cleaning a water recycling device according to anyone of clauses 9 to 11, wherein said water recycling device furthercomprises a heater arrangement placed downstream of said water treatmentarrangement and/or combined with said water treatment arrangement,wherein said step of providing said water recycling device with saidused water, said external water, or said combination of said used waterand said external water comprises a sub-step of heating said used water,said external water, or said combination of said used water and saidexternal water in said heating arrangement.

1. A method for recycling water in a water recycling device, said methodcomprising: receiving used water via a drain; determining a waterquality measure of said used water; if said water quality measure ofsaid used water is above a first quality threshold, feeding said usedwater to a valve arrangement; in said valve arrangement, forming waterto be treated by providing external water, said used water or acombination of said external water and said used water; generatingtreated water by treating said water to be treated using a watertreatment arrangement; and feeding said treated water to an outlet. 2.The method according to claim 1, wherein said step of forming water tobe treated by providing external water, said used water or a combinationof said external water and said used water, comprises sub-steps ofproviding only said external water for forming said water to be treatedif said water quality measure is below said first quality threshold, orproviding only said used water for forming said water to be treated ifsaid water quality measure is above said first quality threshold.
 3. Themethod according to claim 1, wherein said step of forming water to betreated by providing external water, said used water or a combination ofsaid external water and said used water, comprises sub-steps ofproviding only said external water for forming said water to be treatedif said water quality measure is below said first quality threshold anda second quality threshold, providing said combination of said externalwater and said used water for forming said water to be treated if saidwater quality measure is above said first quality threshold but belowsaid second quality threshold, or providing only said used water forforming said water to be treated if said water quality measure is abovesaid first quality threshold and said second quality threshold.
 4. Themethod according to claim 1, wherein said step of generating treatedwater by treating said water to be treated using a water treatmentarrangement comprises sub-steps of filtering said water to be treated,and reducing a harmful effect of microorganisms in said water to betreated by using UV light.
 5. A water recycling device comprising: anoutlet configured to output treated water; a drain for collecting usedwater output from said outlet; a return path in liquid communicationwith said drain; a treatment path in liquid communication with saidreturn path and said outlet; an external water path in liquidcommunication with said treatment path, said external water path beingconnected to an external water outlet; a valve arrangement configured toaccept as inputs said used water from said return path and/or externalwater from said external water path, said valve arrangement being placedbetween said return path and said treatment path, said valve arrangementbeing configured to direct said inputs to said treatment path, saidvalve arrangement being configured to mix said external water with saidwater from said return path; a circulation pump for providing a flow insaid water recycling device; and a water treatment arrangement placeddownstream of said valve arrangement.
 6. The water recycling deviceaccording to claim 5, further comprising a heating arrangement placeddownstream of and/or combined with said water treatment arrangement,wherein said heating arrangement is combined with a UV light treatmentarrangement into a single piece of equipment.
 7. The water recyclingdevice according to claim 5, wherein said water treatment arrangementcomprises a filter arrangement.
 8. The water recycling device accordingto claim 5, further comprising a valve discard path configured todischarge water from said water recycling device, wherein said valvearrangement is further configured to direct said water from said returnpath to said valve discard path.
 9. The water recycling device accordingto claim 5, wherein said valve arrangement comprises at least a firstand a second valve arrangement, wherein said first valve is configuredto accept as input said used water from said return path, said firstvalve arrangement being configured to direct said used water from saidreturn path to said treatment path, and wherein said second valvearrangement accepts as input said external water from said externalwater path, said second valve arrangement being configured to directsaid external water to said treatment path.
 10. The water recyclingdevice according to claim 5, wherein said drain comprises a draindiscard path configured to discharge used water from said waterrecycling device.
 11. A water recirculating shower comprising a waterrecycling device according to claim 5.